Merging upstream version 1.73.0+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

6 files changed, 28 insertions, 19 deletions

diff --git a/compiler/rustc_builtin_macros/src/deriving/clone.rs b/compiler/rustc_builtin_macros/src/deriving/clone.rs
index 9ba98d0a5..b468abe32 100644
--- a/compiler/rustc_builtin_macros/src/deriving/clone.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/clone.rs
@@ -144,7 +144,7 @@ fn cs_clone_simple(
             }
             _ => cx.span_bug(
                 trait_span,
-                format!("unexpected substructure in simple `derive({})`", name),
+                format!("unexpected substructure in simple `derive({name})`"),
             ),
         }
     }
@@ -178,10 +178,10 @@ fn cs_clone(
             vdata = &variant.data;
         }
         EnumTag(..) | AllFieldlessEnum(..) => {
-            cx.span_bug(trait_span, format!("enum tags in `derive({})`", name,))
+            cx.span_bug(trait_span, format!("enum tags in `derive({name})`",))
         }
         StaticEnum(..) | StaticStruct(..) => {
-            cx.span_bug(trait_span, format!("associated function in `derive({})`", name))
+            cx.span_bug(trait_span, format!("associated function in `derive({name})`"))
         }
     }
 
@@ -193,7 +193,7 @@ fn cs_clone(
                     let Some(ident) = field.name else {
                         cx.span_bug(
                             trait_span,
-                            format!("unnamed field in normal struct in `derive({})`", name,),
+                            format!("unnamed field in normal struct in `derive({name})`",),
                         );
                     };
                     let call = subcall(cx, field);
diff --git a/compiler/rustc_builtin_macros/src/deriving/cmp/ord.rs b/compiler/rustc_builtin_macros/src/deriving/cmp/ord.rs
index 4401cf8a9..ea81cee78 100644
--- a/compiler/rustc_builtin_macros/src/deriving/cmp/ord.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/cmp/ord.rs
@@ -61,8 +61,8 @@ pub fn cs_cmp(cx: &mut ExtCtxt<'_>, span: Span, substr: &Substructure<'_>) -> Bl
         |cx, fold| match fold {
             CsFold::Single(field) => {
                 let [other_expr] = &field.other_selflike_exprs[..] else {
-                        cx.span_bug(field.span, "not exactly 2 arguments in `derive(Ord)`");
-                    };
+                    cx.span_bug(field.span, "not exactly 2 arguments in `derive(Ord)`");
+                };
                 let args = thin_vec![field.self_expr.clone(), other_expr.clone()];
                 cx.expr_call_global(field.span, cmp_path.clone(), args)
             }
diff --git a/compiler/rustc_builtin_macros/src/deriving/cmp/partial_ord.rs b/compiler/rustc_builtin_macros/src/deriving/cmp/partial_ord.rs
index 54b6cb7d7..a5b3a504e 100644
--- a/compiler/rustc_builtin_macros/src/deriving/cmp/partial_ord.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/cmp/partial_ord.rs
@@ -94,8 +94,8 @@ fn cs_partial_cmp(
         |cx, fold| match fold {
             CsFold::Single(field) => {
                 let [other_expr] = &field.other_selflike_exprs[..] else {
-                        cx.span_bug(field.span, "not exactly 2 arguments in `derive(Ord)`");
-                    };
+                    cx.span_bug(field.span, "not exactly 2 arguments in `derive(Ord)`");
+                };
                 let args = thin_vec![field.self_expr.clone(), other_expr.clone()];
                 cx.expr_call_global(field.span, partial_cmp_path.clone(), args)
             }
diff --git a/compiler/rustc_builtin_macros/src/deriving/decodable.rs b/compiler/rustc_builtin_macros/src/deriving/decodable.rs
index 3921533c8..bcf11cb4c 100644
--- a/compiler/rustc_builtin_macros/src/deriving/decodable.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/decodable.rs
@@ -204,7 +204,7 @@ where
                 let fields = fields
                     .iter()
                     .enumerate()
-                    .map(|(i, &span)| getarg(cx, span, Symbol::intern(&format!("_field{}", i)), i))
+                    .map(|(i, &span)| getarg(cx, span, Symbol::intern(&format!("_field{i}")), i))
                     .collect();
 
                 cx.expr_call(trait_span, path_expr, fields)
diff --git a/compiler/rustc_builtin_macros/src/deriving/encodable.rs b/compiler/rustc_builtin_macros/src/deriving/encodable.rs
index a3b11309d..2dc20c324 100644
--- a/compiler/rustc_builtin_macros/src/deriving/encodable.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/encodable.rs
@@ -173,7 +173,7 @@ fn encodable_substructure(
             for (i, &FieldInfo { name, ref self_expr, span, .. }) in fields.iter().enumerate() {
                 let name = match name {
                     Some(id) => id.name,
-                    None => Symbol::intern(&format!("_field{}", i)),
+                    None => Symbol::intern(&format!("_field{i}")),
                 };
                 let self_ref = cx.expr_addr_of(span, self_expr.clone());
                 let enc =
diff --git a/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs b/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs
index 4ba09335c..6597ee3cf 100644
--- a/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs
+++ b/compiler/rustc_builtin_macros/src/deriving/generic/mod.rs
@@ -1134,9 +1134,14 @@ impl<'a> MethodDef<'a> {
         trait_: &TraitDef<'b>,
         enum_def: &'b EnumDef,
         type_ident: Ident,
-        selflike_args: ThinVec<P<Expr>>,
+        mut selflike_args: ThinVec<P<Expr>>,
         nonselflike_args: &[P<Expr>],
     ) -> BlockOrExpr {
+        assert!(
+            !selflike_args.is_empty(),
+            "static methods must use `expand_static_enum_method_body`",
+        );
+
         let span = trait_.span;
         let variants = &enum_def.variants;
 
@@ -1144,10 +1149,15 @@ impl<'a> MethodDef<'a> {
         let unify_fieldless_variants =
             self.fieldless_variants_strategy == FieldlessVariantsStrategy::Unify;
 
-        // There is no sensible code to be generated for *any* deriving on a
-        // zero-variant enum. So we just generate a failing expression.
+        // For zero-variant enum, this function body is unreachable. Generate
+        // `match *self {}`. This produces machine code identical to `unsafe {
+        // core::intrinsics::unreachable() }` while being safe and stable.
         if variants.is_empty() {
-            return BlockOrExpr(ThinVec::new(), Some(deriving::call_unreachable(cx, span)));
+            selflike_args.truncate(1);
+            let match_arg = cx.expr_deref(span, selflike_args.pop().unwrap());
+            let match_arms = ThinVec::new();
+            let expr = cx.expr_match(span, match_arg, match_arms);
+            return BlockOrExpr(ThinVec::new(), Some(expr));
         }
 
         let prefixes = iter::once("__self".to_string())
@@ -1156,7 +1166,7 @@ impl<'a> MethodDef<'a> {
                     .iter()
                     .enumerate()
                     .skip(1)
-                    .map(|(arg_count, _selflike_arg)| format!("__arg{}", arg_count)),
+                    .map(|(arg_count, _selflike_arg)| format!("__arg{arg_count}")),
             )
             .collect::<Vec<String>>();
 
@@ -1171,7 +1181,7 @@ impl<'a> MethodDef<'a> {
         let get_tag_pieces = |cx: &ExtCtxt<'_>| {
             let tag_idents: Vec<_> = prefixes
                 .iter()
-                .map(|name| Ident::from_str_and_span(&format!("{}_tag", name), span))
+                .map(|name| Ident::from_str_and_span(&format!("{name}_tag"), span))
                 .collect();
 
             let mut tag_exprs: Vec<_> = tag_idents
@@ -1511,7 +1521,7 @@ impl<'a> TraitDef<'a> {
     }
 
     fn mk_pattern_ident(&self, prefix: &str, i: usize) -> Ident {
-        Ident::from_str_and_span(&format!("{}_{}", prefix, i), self.span)
+        Ident::from_str_and_span(&format!("{prefix}_{i}"), self.span)
     }
 
     fn create_struct_pattern_fields(
@@ -1592,8 +1602,7 @@ impl<'a> TraitDef<'a> {
                                 sp,
                                 ast::CRATE_NODE_ID,
                                 format!(
-                                    "{} slice in a packed struct that derives a built-in trait",
-                                    ty
+                                    "{ty} slice in a packed struct that derives a built-in trait"
                                 ),
                                 rustc_lint_defs::BuiltinLintDiagnostics::ByteSliceInPackedStructWithDerive
                             );